Lettuce variety ‘Cavendish’

ABSTRACT

New lettuce variety designated ‘Cavendish’ is described. ‘Cavendish’ is a lettuce variety varieties exhibiting stability and uniformity.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No.62/539,198, filed Jul. 31, 2017, which is hereby incorporated byreference in its entirety.

FIELD OF THE INVENTION

The present invention relates to the field of plant breeding. Inparticular, this invention relates to new lettuce, Lactuca sativavarieties designated ‘Cavendish’, ‘Clearwater’, and ‘Pensacola’.

BACKGROUND OF THE INVENTION

Cultivated forms of lettuce belong to the highly polymorphic speciesLactuca sativa that is grown for its edible head and leaves. As a crop,lettuce is grown commercially wherever environmental conditions permitthe production of an economically viable yield. For planting purposes,the lettuce season is typically divided into three categories (i.e.,early, mid, and late), with coastal areas planting from January toAugust, and desert regions planting from August to December. Freshlettuce is consumed nearly exclusively as fresh, raw product andoccasionally as a cooked vegetable.

Lactuca sativa is in the Cichorieae tribe of the Asteraceae (Compositae)family. Lettuce is related to chicory, sunflower, aster, dandelion,artichoke, and chrysanthemum. Sativa is one of about 300 species in thegenus Lactuca. There are seven different morphological types of lettuce.The crisphead group includes the iceberg and batavian types. Iceberglettuce has a large, firm head with a crisp texture and a white orcreamy yellow interior. The batavian lettuce predates the iceberg typeand has a smaller and less firm head. The butterhead group has a small,soft head with an almost oily texture. The romaine, also known as coslettuce, has elongated upright leaves forming a loose, loaf-shaped headand the outer leaves are usually dark green. Leaf lettuce, also known ascutting lettuce, comes in many varieties, none of which form a head, andinclude the green oak leaf variety. Latin lettuce, also known asgrasse-type lettuce, looks like a cross between romaine and butterhead.Stem lettuce has long, narrow leaves and thick, edible stems. Oilseedlettuce is a type grown for its large seeds that are pressed to obtainoil.

Lettuce is an increasingly popular crop. Worldwide lettuce consumptioncontinues to increase. As a result of this demand, there is a continuedneed for new lettuce varieties. In particular, there is a need forimproved lettuce varieties that are stable, high yielding, andagronomically sound.

SUMMARY OF THE INVENTION

In order to meet these needs, the present invention is directed toimproved lettuce varieties.

In one embodiment, the present invention is directed to lettuce, Lactucasativa, seed designated as ‘Cavendish’ having NCIMB Accession Number43193. In one embodiment, the present invention is directed to a Lactucasativa lettuce plant and parts isolated therefrom produced by growing‘Cavendish’ lettuce seed. In another embodiment, the present inventionis directed to a Lactuca sativa plant and parts isolated therefromhaving all the physiological and morphological characteristics of aLactuca sativa plant produced by growing ‘Cavendish’ lettuce seed havingNCIMB Accession Number 43193. In still another embodiment, the presentinvention is directed to an F₁ hybrid Lactuca sativa lettuce seed,plants grown from the seed, and a head isolated therefrom having‘Cavendish’ as a parent, where ‘Cavendish’ is grown from ‘Cavendish’lettuce seed having NCIMB Accession Number 43193.

Lettuce plant parts include lettuce heads, lettuce leaves, parts oflettuce leaves, pollen, ovules, flowers, and the like. In anotherembodiment, the present invention is further directed to lettuce heads,lettuce leaves, parts of lettuce leaves, flowers, pollen, and ovulesisolated from ‘Cavendish’ lettuce plants. In another embodiment, thepresent invention is further directed to tissue culture of ‘Cavendish’lettuce plants, and to lettuce plants regenerated from the tissueculture, where the plant has all of the morphological and physiologicalcharacteristics of ‘Cavendish’ lettuce plants.

In still another embodiment, the present invention is further directedto packaging material containing ‘Cavendish’ plant parts. Such packagingmaterial includes but is not limited to boxes, plastic bags, etc. The‘Cavendish’ plant parts may be combined with other plant parts of otherplant varieties.

In yet another embodiment, the present invention is further directed toa method of selecting lettuce plants, by a) growing ‘Cavendish’ lettuceplants where the ‘Cavendish’ plants are grown from lettuce seed havingNCIMB Accession Number 43193 and b) selecting a plant from step a). Inanother embodiment, the present invention is further directed to lettuceplants, plant parts and seeds produced by the lettuce plants where thelettuce plants are isolated by the selection method of the invention.

In another embodiment, the present invention is further directed to amethod of breeding lettuce plants by crossing a lettuce plant with aplant grown from ‘Cavendish’ lettuce seed having NCIMB Accession Number43193. In still another embodiment, the present invention is furtherdirected to lettuce plants, lettuce parts from the lettuce plants, andseeds produced therefrom where the lettuce plant is isolated by thebreeding method of the invention.

In another embodiment, the present invention is directed to methods forproducing a male sterile lettuce plant by introducing a nucleic acidmolecule that confers male sterility into a lettuce plant produced bygrowing ‘Cavendish’ lettuce seed, and to male sterile lettuce plantsproduced by such methods.

In another embodiment, the present invention is directed to methods ofproducing an herbicide resistant lettuce plant by introducing a geneconferring herbicide resistance into a lettuce plant produced by growing‘Cavendish’ lettuce seed, where the gene confers resistance to anherbicide selected from glyphosate, sulfonylurea, imidazolinone,dicamba, glufosinate, phenoxy proprionic acid, L-phosphinothricin,cyclohexone, cyclohexanedione, triazine, and benzonitrile. Certainembodiments are also directed to herbicide resistant lettuce plantsproduced by such methods.

In another embodiment, the present invention is directed to methods ofproducing a pest or insect resistant lettuce plan by introducing a geneconferring pest or insect resistance into a lettuce plant produced bygrowing ‘Cavendish’ lettuce seed, and to pest or insect resistantlettuce plants produced by such methods. In certain embodiments, thegene conferring pest or insect resistance encodes a Bacillusthuringiensis endotoxin.

In another embodiment, the present invention is directed to methods ofproducing a disease resistant lettuce plant by introducing a geneconferring disease resistance into a lettuce plant produced by growing‘Cavendish’ lettuce seed, and to disease resistant lettuce plantsproduced by such methods.

In another embodiment, the present invention is directed to methods ofproducing a lettuce plant with a value-added trait by introducing a geneconferring a value-added trait into a lettuce plant produced by growing‘Cavendish’ lettuce seed, where the gene encodes a protein selected froma ferritin, a nitrate reductase, and a monellin. Certain embodiments arealso directed to lettuce plants having a value-added trait produced bysuch methods.

In another embodiment, the present invention is directed to methods ofintroducing a desired trait into lettuce variety ‘Cavendish’, by: (a)crossing a ‘Cavendish’ plant, where a sample of ‘Cavendish’ lettuce seedwas deposited under NCIMB Accession Number 43193, with a plant ofanother lettuce variety that contains a desired trait to produce progenyplants, where the desired trait is selected from male sterility;herbicide resistance; insect or pest resistance; modified bolting; andresistance to bacterial disease, fungal disease or viral disease; (b)selecting one or more progeny plants that have the desired trait; (c)backcrossing the selected progeny plants with a ‘Cavendish’ plant toproduce backcross progeny plants; (d) selecting for backcross progenyplants that have the desired trait and all of the physiological andmorphological characteristics of lettuce variety ‘Cavendish’; and (e)repeating steps (c) and (d) two or more times in succession to produceselected third or higher backcross progeny plants that comprise thedesired trait. Certain embodiments are also directed to lettuce plantsproduced by such methods, where the plants have the desired trait andall of the physiological and morphological characteristics of lettucevariety ‘Cavendish’. In certain embodiments, the desired trait isherbicide resistance and the resistance is conferred to an herbicideselected from glyphosate, sulfonylurea, imidazolinone, dicamba,glufosinate, phenoxy proprionic acid, L-phosphinothricin, cyclohexone,cyclohexanedione, triazine, and benzonitrile.

In another embodiment, the present invention provides for single geneconverted plants of ‘Cavendish’. The single transferred gene maypreferably be a dominant or recessive allele. Preferably, the singletransferred gene will confer such traits as male sterility, herbicideresistance, insect or pest resistance, modified fatty acid metabolism,modified carbohydrate metabolism, resistance for bacterial, fungal, orviral disease, male fertility, enhanced nutritional quality, andindustrial usage.

In one embodiment, the present invention is directed to lettuce, Lactucasativa, seed designated as ‘Clearwater’ having NCIMB Accession NumberX2. In one embodiment, the present invention is directed to a Lactucasativa lettuce plant and parts isolated therefrom produced by growing‘Clearwater’ lettuce seed. In another embodiment, the present inventionis directed to a Lactuca sativa plant and parts isolated therefromhaving all the physiological and morphological characteristics of aLactuca sativa plant produced by growing ‘Clearwater’ lettuce seedhaving NCIMB Accession Number X2. In still another embodiment, thepresent invention is directed to an F₁ hybrid Lactuca sativa lettuceseed, plants grown from the seed, and a head isolated therefrom having‘Clearwater’ as a parent, where ‘Clearwater’ is grown from ‘Clearwater’lettuce seed having NCIMB Accession Number X2.

Lettuce plant parts include lettuce heads, lettuce leaves, parts oflettuce leaves, pollen, ovules, flowers, and the like. In anotherembodiment, the present invention is further directed to lettuce heads,lettuce leaves, parts of lettuce leaves, flowers, pollen, and ovulesisolated from ‘Clearwater’ lettuce plants. In another embodiment, thepresent invention is further directed to tissue culture of ‘Clearwater’lettuce plants, and to lettuce plants regenerated from the tissueculture, where the plant has all of the morphological and physiologicalcharacteristics of ‘Clearwater’ lettuce plants.

In still another embodiment, the present invention is further directedto packaging material containing ‘Clearwater’ plant parts. Suchpackaging material includes but is not limited to boxes, plastic bags,etc. The ‘Clearwater’ plant parts may be combined with other plant partsof other plant varieties.

In yet another embodiment, the present invention is further directed toa method of selecting lettuce plants, by a) growing ‘Clearwater’ lettuceplants where the ‘Clearwater’ plants are grown from lettuce seed havingNCIMB Accession Number X2 and b) selecting a plant from step a). Inanother embodiment, the present invention is further directed to lettuceplants, plant parts and seeds produced by the lettuce plants where thelettuce plants are isolated by the selection method of the invention.

In another embodiment, the present invention is further directed to amethod of breeding lettuce plants by crossing a lettuce plant with aplant grown from ‘Clearwater’ lettuce seed having NCIMB Accession NumberX2. In still another embodiment, the present invention is furtherdirected to lettuce plants, lettuce parts from the lettuce plants, andseeds produced therefrom where the lettuce plant is isolated by thebreeding method of the invention.

In another embodiment, the present invention is directed to methods forproducing a male sterile lettuce plant by introducing a nucleic acidmolecule that confers male sterility into a lettuce plant produced bygrowing ‘Clearwater’ lettuce seed, and to male sterile lettuce plantsproduced by such methods.

In another embodiment, the present invention is directed to methods ofproducing an herbicide resistant lettuce plant by introducing a geneconferring herbicide resistance into a lettuce plant produced by growing‘Clearwater’ lettuce seed, where the gene confers resistance to anherbicide selected from glyphosate, sulfonylurea, imidazolinone,dicamba, glufosinate, phenoxy proprionic acid, L-phosphinothricin,cyclohexone, cyclohexanedione, triazine, and benzonitrile. Certainembodiments are also directed to herbicide resistant lettuce plantsproduced by such methods.

In another embodiment, the present invention is directed to methods ofproducing a pest or insect resistant lettuce plan by introducing a geneconferring pest or insect resistance into a lettuce plant produced bygrowing ‘Clearwater’ lettuce seed, and to pest or insect resistantlettuce plants produced by such methods. In certain embodiments, thegene conferring pest or insect resistance encodes a Bacillusthuringiensis endotoxin.

In another embodiment, the present invention is directed to methods ofproducing a disease resistant lettuce plant by introducing a geneconferring disease resistance into a lettuce plant produced by growing‘Clearwater’ lettuce seed, and to disease resistant lettuce plantsproduced by such methods.

In another embodiment, the present invention is directed to methods ofproducing a lettuce plant with a value-added trait by introducing a geneconferring a value-added trait into a lettuce plant produced by growing‘Clearwater’ lettuce seed, where the gene encodes a protein selectedfrom a ferritin, a nitrate reductase, and a monellin. Certainembodiments are also directed to lettuce plants having a value-addedtrait produced by such methods.

In another embodiment, the present invention is directed to methods ofintroducing a desired trait into lettuce variety ‘Clearwater’, by: (a)crossing a ‘Clearwater’ plant, where a sample of ‘Clearwater’ lettuceseed was deposited under NCIMB Accession Number X2, with a plant ofanother lettuce variety that contains a desired trait to produce progenyplants, where the desired trait is selected from male sterility;herbicide resistance; insect or pest resistance; modified bolting; andresistance to bacterial disease, fungal disease or viral disease; (b)selecting one or more progeny plants that have the desired trait; (c)backcrossing the selected progeny plants with a ‘Clearwater’ plant toproduce backcross progeny plants; (d) selecting for backcross progenyplants that have the desired trait and all of the physiological andmorphological characteristics of lettuce variety ‘Clearwater’; and (e)repeating steps (c) and (d) two or more times in succession to produceselected third or higher backcross progeny plants that comprise thedesired trait. Certain embodiments are also directed to lettuce plantsproduced by such methods, where the plants have the desired trait andall of the physiological and morphological characteristics of lettucevariety ‘Clearwater’. In certain embodiments, the desired trait isherbicide resistance and the resistance is conferred to an herbicideselected from glyphosate, sulfonylurea, imidazolinone, dicamba,glufosinate, phenoxy proprionic acid, L-phosphinothricin, cyclohexone,cyclohexanedione, triazine, and benzonitrile.

In another embodiment, the present invention provides for single geneconverted plants of ‘Clearwater’. The single transferred gene maypreferably be a dominant or recessive allele. Preferably, the singletransferred gene will confer such traits as male sterility, herbicideresistance, insect or pest resistance, modified fatty acid metabolism,modified carbohydrate metabolism, resistance for bacterial, fungal, orviral disease, male fertility, enhanced nutritional quality, andindustrial usage.

In one embodiment, the present invention is directed to lettuce, Lactucasativa, seed designated as ‘Pensacola’ having NCIMB Accession Number X3.In one embodiment, the present invention is directed to a Lactuca sativalettuce plant and parts isolated therefrom produced by growing‘Pensacola’ lettuce seed. In another embodiment, the present inventionis directed to a Lactuca sativa plant and parts isolated therefromhaving all the physiological and morphological characteristics of aLactuca sativa plant produced by growing ‘Pensacola’ lettuce seed havingNCIMB Accession Number X3. In still another embodiment, the presentinvention is directed to an F₁ hybrid Lactuca sativa lettuce seed,plants grown from the seed, and a head isolated therefrom having‘Pensacola’ as a parent, where ‘Pensacola’ is grown from ‘Pensacola’lettuce seed having NCIMB Accession Number X3.

Lettuce plant parts include lettuce heads, lettuce leaves, parts oflettuce leaves, pollen, ovules, flowers, and the like. In anotherembodiment, the present invention is further directed to lettuce heads,lettuce leaves, parts of lettuce leaves, flowers, pollen, and ovulesisolated from ‘Pensacola’ lettuce plants. In another embodiment, thepresent invention is further directed to tissue culture of ‘Pensacola’lettuce plants, and to lettuce plants regenerated from the tissueculture, where the plant has all of the morphological and physiologicalcharacteristics of ‘Pensacola’ lettuce plants.

In still another embodiment, the present invention is further directedto packaging material containing ‘Pensacola’ plant parts. Such packagingmaterial includes but is not limited to boxes, plastic bags, etc. The‘Pensacola’ plant parts may be combined with other plant parts of otherplant varieties.

In yet another embodiment, the present invention is further directed toa method of selecting lettuce plants, by a) growing ‘Pensacola’ lettuceplants where the ‘Pensacola’ plants are grown from lettuce seed havingNCIMB Accession Number X3 and b) selecting a plant from step a). Inanother embodiment, the present invention is further directed to lettuceplants, plant parts and seeds produced by the lettuce plants where thelettuce plants are isolated by the selection method of the invention.

In another embodiment, the present invention is further directed to amethod of breeding lettuce plants by crossing a lettuce plant with aplant grown from ‘Pensacola’ lettuce seed having NCIMB Accession NumberX3. In still another embodiment, the present invention is furtherdirected to lettuce plants, lettuce parts from the lettuce plants, andseeds produced therefrom where the lettuce plant is isolated by thebreeding method of the invention.

In another embodiment, the present invention is directed to methods forproducing a male sterile lettuce plant by introducing a nucleic acidmolecule that confers male sterility into a lettuce plant produced bygrowing ‘Pensacola’ lettuce seed, and to male sterile lettuce plantsproduced by such methods.

In another embodiment, the present invention is directed to methods ofproducing an herbicide resistant lettuce plant by introducing a geneconferring herbicide resistance into a lettuce plant produced by growing‘Pensacola’ lettuce seed, where the gene confers resistance to anherbicide selected from glyphosate, sulfonylurea, imidazolinone,dicamba, glufosinate, phenoxy proprionic acid, L-phosphinothricin,cyclohexone, cyclohexanedione, triazine, and benzonitrile. Certainembodiments are also directed to herbicide resistant lettuce plantsproduced by such methods.

In another embodiment, the present invention is directed to methods ofproducing a pest or insect resistant lettuce plan by introducing a geneconferring pest or insect resistance into a lettuce plant produced bygrowing ‘Pensacola’ lettuce seed, and to pest or insect resistantlettuce plants produced by such methods. In certain embodiments, thegene conferring pest or insect resistance encodes a Bacillusthuringiensis endotoxin.

In another embodiment, the present invention is directed to methods ofproducing a disease resistant lettuce plant by introducing a geneconferring disease resistance into a lettuce plant produced by growing‘Pensacola’ lettuce seed, and to disease resistant lettuce plantsproduced by such methods.

In another embodiment, the present invention is directed to methods ofproducing a lettuce plant with a value-added trait by introducing a geneconferring a value-added trait into a lettuce plant produced by growing‘Pensacola’ lettuce seed, where the gene encodes a protein selected froma ferritin, a nitrate reductase, and a monellin. Certain embodiments arealso directed to lettuce plants having a value-added trait produced bysuch methods.

In another embodiment, the present invention is directed to methods ofintroducing a desired trait into lettuce variety ‘Pensacola’, by: (a)crossing a ‘Pensacola’ plant, where a sample of ‘Pensacola’ lettuce seedwas deposited under NCIMB Accession Number X3, with a plant of anotherlettuce variety that contains a desired trait to produce progeny plants,where the desired trait is selected from male sterility; herbicideresistance; insect or pest resistance; modified bolting; and resistanceto bacterial disease, fungal disease or viral disease; (b) selecting oneor more progeny plants that have the desired trait; (c) backcrossing theselected progeny plants with a ‘Pensacola’ plant to produce backcrossprogeny plants; (d) selecting for backcross progeny plants that have thedesired trait and all of the physiological and morphologicalcharacteristics of lettuce variety ‘Pensacola’; and (e) repeating steps(c) and (d) two or more times in succession to produce selected third orhigher backcross progeny plants that comprise the desired trait. Certainembodiments are also directed to lettuce plants produced by suchmethods, where the plants have the desired trait and all of thephysiological and morphological characteristics of lettuce variety‘Pensacola’. In certain embodiments, the desired trait is herbicideresistance and the resistance is conferred to an herbicide selected fromglyphosate, sulfonylurea, imidazolinone, dicamba, glufosinate, phenoxyproprionic acid, L-phosphinothricin, cyclohexone, cyclohexanedione,triazine, and benzonitrile.

In another embodiment, the present invention provides for single geneconverted plants of ‘Pensacola’. The single transferred gene maypreferably be a dominant or recessive allele. Preferably, the singletransferred gene will confer such traits as male sterility, herbicideresistance, insect or pest resistance, modified fatty acid metabolism,modified carbohydrate metabolism, resistance for bacterial, fungal, orviral disease, male fertility, enhanced nutritional quality, andindustrial usage.

In a further embodiment, the present invention relates to methods fordeveloping lettuce plants in a lettuce plant breeding program usingplant breeding techniques including recurrent selection, backcrossing,pedigree breeding, restriction fragment length polymorphism enhancedselection, and genetic marker enhanced selection. Seeds, lettuce plants,and parts thereof, produced by such breeding methods are also part ofthe invention.

In addition to the exemplary aspects and embodiments described above,further aspects and embodiments will become apparent by reference bystudy of the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawings will be provided by the office upon request and paymentof the necessary fee.

FIG. 1A shows a plant of lettuce variety ‘Cavendish’. FIG. 1B showsleaves of lettuce variety ‘Cavendish’. FIG. 1C to 111 show a comparisonbetween lettuce varieties ‘Cavendish’, ‘Poneloya’, and ‘Sadawi’. FIG. 1Cshows leaves of lettuce variety ‘Cavendish’. FIG. 1D shows leaves oflettuce variety ‘Poneloya’. FIG. 1E shows leaves of lettuce variety‘Sadawi’. FIG. 1F shows a plant of lettuce variety ‘Cavendish’. FIG. 1Gshows a plant of lettuce variety ‘Poneloya’. FIG. 1H shows a plant oflettuce variety ‘Sadawi’.

FIG. 2A shows a plant of lettuce variety ‘Clearwater’. FIG. 2B showsleaves of lettuce variety ‘Clearwater’. FIG. 2C to 2F show a comparisonbetween lettuce varieties ‘Clearwater’ and ‘Bolsachica’. FIG. 2C showsleaves of lettuce variety ‘Clearwater’. FIG. 2D shows leaves of lettucevariety ‘Bolsachica’. FIG. 2E shows a plant of lettuce variety‘Clearwater’. FIG. 2F shows a plant of lettuce variety ‘Bolsachica’.

FIG. 3A shows a plant of lettuce variety ‘Pensacola’. FIG. 3B showsleaves of lettuce variety ‘Pensacola’. FIG. 3C to 3F show a comparisonbetween lettuce varieties ‘Pensacola’ and ‘Palosta’. FIG. 3C showsleaves of lettuce variety ‘Pensacola’. FIG. 3D shows leaves of lettucevariety ‘Palosta’. FIG. 3E shows a plant of lettuce variety ‘Pensacola’.FIG. 3F shows a plant of lettuce variety ‘Palosta’.

DETAILED DESCRIPTION OF THE INVENTION

There are numerous steps in the development of novel, desirable lettucegermplasm. Plant breeding begins with the analysis of problems andweaknesses of current lettuce germplasms, the establishment of programgoals, and the definition of specific breeding objectives. The next stepis selection of germplasm that possess the traits to meet the programgoals. The goal is to combine in a single variety or hybrid an improvedcombination of desirable traits from the parental germplasm. Theseimportant traits may include increased head size and weight, higher seedyield, improved color, resistance to diseases and insects, tolerance todrought and heat, and better agronomic quality.

Choice of breeding or selection methods can depend on the mode of plantreproduction, the heritability of the trait(s) being improved, and thetype of variety used commercially (e.g., F₁ hybrid variety, purelinevariety, etc.). For highly heritable traits, a choice of superiorindividual plants evaluated at a single location will be effective,whereas for traits with low heritability, selection should be based onmean values obtained from replicated evaluations of families of relatedplants. Popular selection methods commonly include pedigree selection,modified pedigree selection, mass selection, and recurrent selection.

The complexity of inheritance influences choice of the breeding method.Backcross breeding is used to transfer one or a few favorable genes fora highly heritable trait into a desirable variety. This approach hasbeen used extensively for breeding disease-resistant varieties. Variousrecurrent selection techniques are used to improve quantitativelyinherited traits controlled by numerous genes. The use of recurrentselection in self-pollinating crops depends on the ease of pollination,the frequency of successful hybrids from each pollination, and thenumber of hybrid offspring from each successful cross.

Each breeding program may include a periodic, objective evaluation ofthe efficiency of the breeding procedure. Evaluation criteria varydepending on the goal and objectives, and can include gain fromselection per year based on comparisons to an appropriate standard, theoverall value of the advanced breeding lines, and the number ofsuccessful varieties produced per unit of input (e.g., per year, perdollar expended, etc.).

Promising advanced breeding lines may be thoroughly tested and comparedto appropriate standards in environments representative of thecommercial target area(s) for at least three years. The best lines canthen be candidates for new commercial varieties. Those still deficientin a few traits may be used as parents to produce new populations forfurther selection. These processes, which lead to the final step ofmarketing and distribution, may take from ten to twenty years from thetime the first cross or selection is made.

One goal of lettuce plant breeding is to develop new, unique, andgenetically superior lettuce varieties. A breeder can initially selectand crosses two or more parental lines, followed by repeated selfing andselection, producing many new genetic combinations. Moreover, a breedercan generate multiple different genetic combinations by crossing,selfing, and mutations. A plant breeder can then select which germplasmsto advance to the next generation. These germplasms may then be grownunder different geographical, climatic, and soil conditions, and furtherselections can be made during, and at the end of, the growing season.

The development of commercial lettuce varieties thus requires thedevelopment of parental lettuce varieties, the crossing of thesevarieties, and the evaluation of the crosses. Pedigree breeding andrecurrent selection breeding methods may be used to develop varietiesfrom breeding populations. Breeding programs can be used to combinedesirable traits from two or more varieties or various broad-basedsources into breeding pools from which new varieties are developed byselfing and selection of desired phenotypes. The new varieties arecrossed with other varieties and the hybrids from these crosses areevaluated to determine which have commercial potential.

Pedigree breeding is generally used for the improvement ofself-pollinating crops or inbred lines of cross-pollinating crops. Twoparents which possess favorable, complementary traits are crossed toproduce an F₁. An F₂ population is produced by selfing one or severalF₁'s or by intercrossing two F₁'s (sib mating). Selection of the bestindividuals is usually begun in the F₂ population. Then, beginning inthe F₃, the best individuals in the best families are selected.Replicated testing of families, or hybrid combinations involvingindividuals of these families, often follows in the F₄ generation toimprove the effectiveness of selection for traits with low heritability.At an advanced stage of inbreeding (i.e., F₆ and F₇), the best lines ormixtures of phenotypically similar lines are tested for potentialrelease as new varieties.

Mass and recurrent selections can be used to improve populations ofeither self- or cross-pollinating crops. A genetically variablepopulation of heterozygous individuals is either identified or createdby intercrossing several different parents. The best plants are selectedbased on individual superiority, outstanding progeny, or excellentcombining ability. The selected plants are intercrossed to produce a newpopulation in which further cycles of selection are continued.

Backcross breeding may be used to transfer genes for a simply inherited,highly heritable trait into a desirable homozygous cultivar or line thatis the recurrent parent. The source of the trait to be transferred iscalled the donor parent. The resulting plant is expected to have theattributes of the recurrent parent (e.g., cultivar) and the desirabletrait transferred from the donor parent. After the initial cross,individuals possessing the phenotype of the donor parent are selectedand repeatedly crossed (backcrossed) to the recurrent parent. Theresulting plant is expected to have the attributes of the recurrentparent (e.g., cultivar) and the desirable trait transferred from thedonor parent.

The single-seed descent procedure in the strict sense refers to plantinga segregating population, harvesting a sample of one seed per plant, andusing the one-seed sample to plant the next generation. When thepopulation has been advanced from the F₂ to the desired level ofinbreeding, the plants from which lines are derived will each trace todifferent F₂ individuals. The number of plants in a population declineswith each generation due to failure of some seeds to germinate or someplants to produce at least one seed. As a result, not all of the F₂plants originally sampled in the population will be represented by aprogeny when generation advance is completed.

In addition to phenotypic observations, the genotype of a plant can alsobe examined. There are many laboratory-based techniques known in the artthat are available for the analysis, comparison and characterization ofplant genotype. Such techniques include, without limitation, IsozymeElectrophoresis, Restriction Fragment Length Polymorphisms (RFLPs),Randomly Amplified Polymorphic DNAs (RAPDs), Arbitrarily PrimedPolymerase Chain Reaction (AP-PCR), DNA Amplification Fingerprinting(DAF), Sequence Characterized Amplified Regions (SCARs), AmplifiedFragment Length polymorphisms (AFLPs), Simple Sequence Repeats (SSRs),which are also referred to as Microsatellites), and Single NucleotidePolymorphisms (SNPs).

Molecular markers can also be used during the breeding process for theselection of qualitative traits. For example, markers closely linked toalleles or markers containing sequences within the actual alleles ofinterest can be used to select plants that contain the alleles ofinterest during a backcrossing breeding program. The markers can also beused to select toward the genome of the recurrent parent and against themarkers of the donor parent. This procedure attempts to minimize theamount of genome from the donor parent that remains in the selectedplants. It can also be used to reduce the number of crosses back to therecurrent parent needed in a backcrossing program. The use of molecularmarkers in the selection process is often called genetic marker enhancedselection or marker-assisted selection. Molecular markers may also beused to identify and exclude certain sources of germplasm as parentalvarieties or ancestors of a plant by providing a means of trackinggenetic profiles through crosses.

Mutation breeding may also be used to introduce new traits into lettucevarieties. Mutations that occur spontaneously or are artificiallyinduced can be useful sources of variability for a plant breeder. Thegoal of artificial mutagenesis is to increase the rate of mutation for adesired characteristic. Mutation rates can be increased by manydifferent means including temperature, long-term seed storage, tissueculture conditions, radiation (such as X-rays, Gamma rays, neutrons,Beta radiation, or ultraviolet radiation), chemical mutagens (such asbase analogs like 5-bromo-uracil), antibiotics, alkylating agents (suchas sulfur mustards, nitrogen mustards, epoxides, ethyleneamines,sulfates, sulfonates, sulfones, or lactones), azide, hydroxylamine,nitrous acid, or acridines. Once a desired trait is observed throughmutagenesis the trait may then be incorporated into existing germplasmby traditional breeding techniques. Details of mutation breeding can befound in Principles of Cultivar Development by Fehr, MacmillanPublishing Company (1993).

The production of double haploids can also be used for the developmentof homozygous varieties in a breeding program. Double haploids areproduced by the doubling of a set of chromosomes from a heterozygousplant to produce a completely homozygous individual. For example, seeWan, et al., Theor. Appl. Genet., 77:889-892 (1989).

Additional non-limiting examples of breeding methods that may be usedinclude, without limitation, those found in Principles of PlantBreeding, John Wiley and Son, pp. 115-161 (1960); Allard (1960);Simmonds (1979); Sneep, et al. (1979); Fehr (1987); and “Carrots andRelated Vegetable Umbelliferae,” Rubatzky, V. E., et al. (1999).

Definitions

In the description that follows, a number of terms are used. In order toprovide a clear and consistent understanding of the specification andclaims, including the scope to be given such terms, the followingdefinitions are provided:

Allele. The allele is any of one or more alternative forms of a gene,all of which relate to one trait or characteristic. In a diploid cell ororganism, the two alleles of a given gene occupy corresponding loci on apair of homologous chromosomes.

Backcrossing. Backcrossing is a process in which a breeder repeatedlycrosses hybrid progeny back to one of the parents, for example, a firstgeneration hybrid F₁ with one of the parental genotype of the F₁ hybrid.

Big Vein virus. Big vein is a disease of lettuce caused by LettuceMirafiori Big Vein Virus which is transmitted by the fungus Olpidiumvirulentus, with vein clearing and leaf shrinkage resulting in plants ofpoor quality and reduced marketable value.

Bolting. The premature development of a flowering stalk, and subsequentseed, before a plant produces a food crop. Bolting is typically causedby late planting.

Bremia lactucae. An oomycete that causes downy mildew in lettuce incooler growing regions.

Core length. Length of the internal lettuce stem measured from the baseof the cut and trimmed head to the tip of the stem.

Corky root. A disease caused by the bacterium Sphingomonassuberifaciens, which causes the entire taproot to become brown, severelycracked, and non-functional.

Cotyledon. One of the first leaves of the embryo of a seed plant;typically one or more in monocotyledons, two in dicotyledons, and two ormore in gymnosperms.

Essentially all the physiological and morphological characteristics. Aplant having essentially all the physiological and morphologicalcharacteristics means a plant having the physiological and morphologicalcharacteristics of the recurrent parent, except for the characteristicsderived from the converted gene.

First water date. The date the seed first receives adequate moisture togerminate. This can and often does equal the planting date.

Gene. As used herein, “gene” refers to a segment of nucleic acid. A genecan be introduced into a genome of a species, whether from a differentspecies or from the same species, using transformation or variousbreeding methods.

Head diameter. Diameter of the cut and trimmed head, sliced vertically,and measured at the widest point perpendicular to the stem.

Head height. Height of the cut and trimmed head, sliced vertically, andmeasured from the base of the cut stem to the cap leaf.

Head weight. Weight of saleable lettuce head, cut and trimmed to marketspecifications.

Lettuce Mosaic virus. A disease that can cause a stunted, deformed, ormottled pattern in young lettuce and yellow, twisted, and deformedleaves in older lettuce.

Maturity date. Maturity refers to the stage when the plants are of fullsize or optimum weight, in marketable form or shape to be of commercialor economic value.

Nasonovia ribisnigri. A lettuce aphid that colonizes the innermostleaves of the lettuce plant, contaminating areas that cannot be treatedeasily with insecticides.

Quantitative Trait Loci. Quantitative Trait Loci (QTL) refers to geneticloci that control to some degree, numerically representable traits thatare usually continuously distributed.

Ratio of head height/diameter. Head height divided by the head diameteris an indication of the head shape; <1 is flattened, 1=round, and >1 ispointed.

Regeneration. Regeneration refers to the development of a plant fromtissue culture.

RHS. RHS refers to the Royal Horticultural Society of England whichpublishes an official botanical color chart quantitatively identifyingcolors according to a defined numbering system. The chart may bepurchased from Royal Horticulture Society Enterprise Ltd., RHS Garden;Wisley, Woking; Surrey GU236QB, UK.

Single gene converted. Single gene converted or conversion plant refersto plants which are developed by a plant breeding technique calledbackcrossing or via genetic engineering where essentially all of thedesired morphological and physiological characteristics of a line arerecovered in addition to the single gene transferred into the line viathe backcrossing technique or via genetic engineering.

Tip burn. Means a browning of the edges or tips of lettuce leaves thatis a physiological response to a lack of calcium.

Wet date. The wet date corresponds to the first planting date oflettuce.

Overview of the Variety ‘Cavendish’

Lettuce variety ‘Cavendish’ is a very dark reddish colored cuttingoakleaf (i.e., cutting) lettuce variety that has an early time toharvest maturity with a longer leaf size having an elliptic shape.‘Cavendish’ has a growing season that includes spring, summer, autumn,and winter, and is suitable for cultivation in the open. Additionally,lettuce variety ‘Cavendish’ is suitable for baby leaf production and isresistant to Bremia lactucae (downy mildew) strains Bl:16-Bl:35 and USI-IX; resistant to lettuce mosaic virus (LMV) strain Ls-1; resistant toNasonovia ribisnigri biotype 0 (Nr:0); and resistant to lettuce dieback(TBSV). FIG. 1A depicts a plant of lettuce variety ‘Cavendish’ and FIG.1B depicts leaves of lettuce variety ‘Cavendish’. Lettuce variety‘Cavendish’ is the result of numerous generations of plant selectionschosen for its early time to harvest maturity, leaf size and shape, andits resistance to Bremia lactucae (downy mildew), lettuce mosaic virus(LMV), Nasonovia ribisnigri biotype 0 (Nr:0); and lettuce dieback(TBSV).

The variety has shown uniformity and stability for the traits, withinthe limits of environmental influence for the traits. It has beenself-pollinated a sufficient number of generations with carefulattention to uniformity of plant type. The line has been increased withcontinued observation for uniformity. No variant traits have beenobserved or are expected in variety ‘Cavendish’.

Objective Description of the Variety ‘Cavendish’

Lettuce variety ‘Cavendish’ has the following morphologic and othercharacteristics:

Plant type: Cutting (i.e., leaf lettuce)

Seed:

Color: Black

Plant:

Diameter: Small to medium

Mature Leaves:

Margin:

-   -   Degree of undulation of margin: Very weak to weak    -   Hue of green color of outer leaves: Reddish    -   Intensity of color of outer leaves: Very dark

Anthocyanin coloration: Present

Pattern of leaf anthocyanin distribution: Diffused and in spots

Intensity of anthocyanin coloration: Very strong

Attitude of leaf at harvest maturity: Erect

Shape of tip of leaf: Acute

Leaf thickness: Thin

Leaf blistering: Weak

Size of leaf blisters: Small

Glossiness of upper side: Medium to strong

Bolting:

Class: Early

Intensity of fasciation: Very weak to weak

Disease/Pest Resistance:

Lettuce mosaic virus (LMV) strain Ls-1: Resistant

Lettuce dieback (TBSV): Resistant

Downy Mildew (Bremia lactucae) (Bl): Resistant to Bl:16-Bl:35 and USI-IX

Pests:

-   -   Nasonovia ribisnigri biotype 0 (Nr:0): Resistant        Comparisons to Other Lettuce Varieties

Table 1 below compares characteristics of lettuce variety ‘Cavendish’with lettuce variety ‘Poneloya’. Column 1 lists the characteristics,column 2 shows the characteristics for lettuce variety ‘Cavendish’, andcolumn 3 shows the characteristics for lettuce variety ‘Poneloya’.

TABLE 1 Characteristic ‘Cavendish’ ‘Poneloya’ Time to harvest maturityEarly Medium Size of leaf Longer leaf Medium Leaf shape Elliptic Broadobrullate Attitude of leaf at 10-12 Erect Semi-erect leaf stage Attitudeof leaf at harvest Erect Semi-erect maturity Thickness of leaf Thin Verythin to thin Shape of tip of leaf Acute Rounded Glossiness of upper sideMedium to strong Strong of leaf Leaf blistering Weak Very weak to weakDegree of undulation of Very weak to Weak leaf blade margin weakAxillary sprouting Absent to very Very weak to weak weak Diameter ofplant Small to medium Small Time of beginning of Early Late boltingunder long day conditions Intensity of fasciation of Very weak to Veryweak flowering plant weak

Table 2 below compares characteristics of lettuce variety ‘Cavendish’with lettuce variety ‘Sadawi’. Column 1 lists the characteristics,column 2 shows the characteristics for lettuce variety ‘Cavendish’, andcolumn 3 shows the characteristics for lettuce variety ‘Sadawi’.

TABLE 2 Characteristic ‘Cavendish’ ‘Sadawi’ Time to harvest maturityEarly Very early LMV resistance Resistant Susceptible Size of leafblisters Small Small to medium Thickness of leaf Thin Thin to mediumGlossiness of upper side Medium to Weak to medium of leaf strongIntensity of leaf Very strong Strong anthocyanin coloration Pattern ofleaf anthocyanin Diffused and in Diffused distribution spots Axillarysprouting Absent to very Medium to weak strong Time of beginning ofEarly Late bolting under long day conditions

Table 3 below shows the results of a trial comparing leaf length, leafwidth, number of leaves per plant, and leaf color of the lettuce variety‘Cavendish’ with lettuce variety ‘Poneloya’. The trial was conducted inAllonnes, France during winter, with a planting density of 1 seed percm, which corresponds to 100 seeds per linear meter.

TABLE 3 Characteristic ‘Cavendish’ ‘Poneloya’ Length of leaf 14 cm 12 cmWidth of leaf  5 cm 4.5 cm  Number of leaves 7 6 per plant Leaf colorRHS N186B RHS N77A

Further distinguishing features are apparent from the comparison oflettuce varieties ‘Cavendish’, ‘Poneloya’, and ‘Sadawi’ depicted in FIG.1C to 1H.

Overview of the Variety ‘Clearwater’

Lettuce variety ‘Clearwater’ is a dark green colored cutting oakleaf(i.e., cutting) lettuce variety that is early to medium bolting and hasa growing speed that is medium. ‘Clearwater’ has a growing season thatincludes spring, summer, autumn, and winter, and is suitable forcultivation in the open. Additionally, lettuce variety ‘Clearwater’ issuitable for baby leaf production and is resistant to Bremia lactucae(downy mildew) strains Bl:16-Bl:35 and US I-IX; resistant to lettucemosaic virus (LMV) strain Ls-1; resistant to Nasonovia ribisnigribiotype 0 (Nr:0); and resistant to lettuce dieback (TBSV). FIG. 2Adepicts a plant of lettuce variety ‘Clearwater’ and FIG. 2B depictsleaves of lettuce variety ‘Clearwater’. Lettuce variety ‘Clearwater’ isthe result of numerous generations of plant selections chosen for itsgrowing speed, and its resistance to Bremia lactucae (downy mildew),lettuce mosaic virus (LMV), Nasonovia ribisnigri biotype 0 (Nr:0), andlettuce dieback (TBSV).

The variety has shown uniformity and stability for the traits, withinthe limits of environmental influence for the traits. It has beenself-pollinated a sufficient number of generations with carefulattention to uniformity of plant type. The line has been increased withcontinued observation for uniformity. No variant traits have beenobserved or are expected in variety ‘Clearwater’.

Objective Description of the Variety ‘Clearwater’

Lettuce variety ‘Clearwater’ has the following morphologic and othercharacteristics:

Plant type: Cutting (i.e., leaf lettuce)

Seed:

Color: White

Mature Leaves:

Margin:

-   -   Hue of green color of outer leaves: Absent    -   Intensity of color of outer leaves: Dark

Anthocyanin coloration: Absent

Bolting:

-   -   Class: Early to medium (e.g., comparable to ‘Bolsachica’)

Disease/Pest Resistance:

Lettuce mosaic virus (LMV) strain Ls-1: Resistant

Lettuce dieback (TBSV): Resistant

Downy Mildew (Bremia lactucae) (Bl): Resistant to Bl:16-Bl:35 and USI-IX

Pests:

-   -   Nasonovia ribisnigri biotype 0 (Nr:0): Resistant        Comparisons to Other Lettuce Varieties

Table 3 below compares a characteristic of lettuce variety ‘Clearwater’with lettuce variety ‘Bolsachica’. Column 1 lists the characteristic,column 2 shows the characteristic for lettuce variety ‘Clearwater’, andcolumn 3 shows the characteristic for lettuce variety ‘Bolsachica’.

TABLE 3 Characteristic ‘Clearwater’ ‘Bolsachica’ Time of beginning ofbolting Medium Early under long day conditions Growing speed Medium FastBremia resistance Resistant to strains Resistant to strains Bl: 16-35,and US Bl: 16-26, Bl: 28, I-IX Bl: 32, and US I-IX

Further distinguishing features are apparent from the comparison oflettuce varieties ‘Clearwater’ and ‘Bolsachica’ depicted in FIG. 2C to2F.

Overview of the Variety ‘Pensacola’

Lettuce variety ‘Pensacola’ is a light green colored grasse (i.e., Latinlettuce) lettuce variety that is medium bolting with weak leafblistering and a growing speed that is medium. ‘Pensacola’ has a growingseason that includes spring, summer, autumn, and winter, and is suitablefor cultivation in the open. Additionally, lettuce variety ‘Pensacola’is suitable for baby leaf production and is resistant to Bremia lactucae(downy mildew) strains Bl:16-Bl:29, Bl:32, Bl:34, and US I-IX; resistantto lettuce mosaic virus (LMV) strain Ls-1; resistant to Nasonoviaribisnigri biotype 0 (Nr:0); and resistant to lettuce dieback (TBSV).FIG. 3A depicts a plant of lettuce variety ‘Pensacola’ and FIG. 3Bdepicts leaves of lettuce variety ‘Pensacola’. Lettuce variety‘Pensacola’ is the result of numerous generations of plant selectionschosen for its weak blistering, growing speed, and its resistance toBremia lactucae (downy mildew), lettuce mosaic virus (LMV), Nasonoviaribisnigri biotype 0 (Nr:0), and lettuce dieback (TBSV).

The variety has shown uniformity and stability for the traits, withinthe limits of environmental influence for the traits. It has beenself-pollinated a sufficient number of generations with carefulattention to uniformity of plant type. The line has been increased withcontinued observation for uniformity. No variant traits have beenobserved or are expected in variety ‘Pensacola’.

Objective Description of the Variety ‘Pensacola’

Lettuce variety ‘Pensacola’ has the following morphologic and othercharacteristics:

Plant type: Grasse (i.e., Latin lettuce)

Seed:

Color: White

Mature Leaves:

Margin:

-   -   Hue of green color of outer leaves: Absent    -   Intensity of color of outer leaves: Light

Anthocyanin coloration: Absent

Bolting:

Class: Medium (e.g., comparable to ‘Palosta’)

Disease/Pest Resistance:

Lettuce mosaic virus (LMV) strain Ls-1: Resistant

Lettuce dieback (TBSV): Resistant

Downy Mildew (Bremia lactucae) (Bl): Resistant to Bl:16-Bl:29, Bl:32,Bl:34, and US I-IX

Pests:

-   -   Nasonovia ribisnigri biotype 0 (Nr:0): Resistant        Comparisons to Other Lettuce Varieties

Table 4 below compares characteristics of lettuce variety ‘Pensacola’with lettuce variety ‘Palosta’. Column 1 lists the characteristics,column 2 shows the characteristics for lettuce variety ‘Pensacola’, andcolumn 3 shows the characteristics for lettuce variety ‘Palosta’.

TABLE 4 Characteristic ‘Pensacola’ ‘Palosta’ Growing speed Fast MediumLeaf blistering Weak Very weak Time of beginning of bolting Medium Earlyunder long day conditions

Further distinguishing features are apparent from the comparison oflettuce varieties ‘Pensacola’ and ‘Palosta’ depicted in FIG. 3C to 3F.

Further Embodiments

Gene Conversions

When the term “lettuce plant” is used in the context of the presentinvention, this also includes any gene conversions of that variety. Theterm “gene converted plant” as used herein refers to those lettuceplants which are developed by backcrossing, genetic engineering, ormutation, where essentially all of the desired morphological andphysiological characteristics of a variety are recovered in addition tothe one or more genes transferred into the variety via the backcrossingtechnique, genetic engineering, or mutation. Backcrossing methods can beused with the present invention to improve or introduce a characteristicinto the variety. The term “backcrossing” as used herein refers to therepeated crossing of a hybrid progeny back to the recurrent parent,i.e., backcrossing 1, 2, 3, 4, 5, 6, 7, 8, 9, or more times to therecurrent parent. The parental lettuce plant which contributes the genefor the desired characteristic is termed the “nonrecurrent” or “donorparent.” This terminology refers to the fact that the nonrecurrentparent is used one time in the backcross protocol and therefore does notrecur. The parental lettuce plant to which the gene or genes from thenonrecurrent parent are transferred is known as the recurrent parent asit is used for several rounds in the backcrossing protocol. Poehlman &Sleper (1994) and Fehr (1993). In a typical backcross protocol, theoriginal variety of interest (recurrent parent) is crossed to a secondvariety (nonrecurrent parent) that carries the gene of interest to betransferred. The resulting progeny from this cross are then crossedagain to the recurrent parent and the process is repeated until alettuce plant is obtained where essentially all of the desiredmorphological and physiological characteristics of the recurrent parentare recovered in the converted plant, in addition to the transferredgene from the nonrecurrent parent.

The selection of a suitable recurrent parent is an important step for asuccessful backcrossing procedure. The goal of a backcross protocol isto alter or substitute a trait or characteristic in the original line.To accomplish this, a gene of the recurrent variety is modified orsubstituted with the desired gene from the nonrecurrent parent, whileretaining essentially all of the rest of the desired genetic, andtherefore the desired physiological and morphological, constitution ofthe original line. The choice of the particular nonrecurrent parent willdepend on the purpose of the backcross. One of the major purposes is toadd some commercially desirable, agronomically important trait to theplant. The exact backcrossing protocol will depend on the characteristicor trait being altered to determine an appropriate testing protocol.Although backcrossing methods are simplified when the characteristicbeing transferred is a dominant allele, a recessive allele may also betransferred. In this instance it may be necessary to introduce a test ofthe progeny to determine if the desired characteristic has beensuccessfully transferred.

Many gene traits have been identified that are not regularly selected inthe development of a new line but that can be improved by backcrossingtechniques. Examples of these traits include, but are not limited to,male sterility, modified fatty acid metabolism, modified carbohydratemetabolism, herbicide resistance, resistance for bacterial, fungal, orviral disease, insect resistance, enhanced nutritional quality,industrial usage, yield stability, and yield enhancement. These genesare generally inherited through the nucleus. Several of these genetraits are described in U.S. Pat. Nos. 5,777,196, 5,948,957, and5,969,212, the disclosures of which are specifically hereby incorporatedby reference.

Tissue Culture

Further reproduction of the variety can occur by tissue culture andregeneration. Tissue culture of various tissues of lettuce andregeneration of plants therefrom is well known and widely published. Forexample, reference may be had to Teng, et al., HortScience, 27:9,1030-1032 (1992); Teng, et al., HortScience, 28:6, 669-1671 (1993);Zhang, et al., Journal of Genetics and Breeding, 46:3, 287-290 (1992);Webb, et al., Plant Cell Tissue and Organ Culture, 38:1, 77-79 (1994);Curtis, et al., Journal of Experimental Botany, 45:279, 1441-1449(1994); Nagata, et al., Journal for the American Society forHorticultural Science, 125:6, 669-672 (2000); and Ibrahim, et al., PlantCell Tissue and Organ Culture, 28(2), 139-145 (1992). It is clear fromthe literature that the state of the art is such that these methods ofobtaining plants are routinely used and have a very high rate ofsuccess. Thus, another aspect of this invention is to provide cellswhich upon growth and differentiation produce lettuce plants having thephysiological and morphological characteristics of variety ‘Cavendish’,‘Clearwater’, or ‘Pensacola’.

As used herein, the term “tissue culture” indicates a compositioncontaining isolated cells of the same or a different type or acollection of such cells organized into parts of a plant. Exemplarytypes of tissue cultures are protoplasts, calli, meristematic cells, andplant cells that can generate tissue culture that are intact in plantsor parts of plants, such as leaves, pollen, embryos, roots, root tips,anthers, pistils, flowers, seeds, petioles, suckers, and the like. Meansfor preparing and maintaining plant tissue culture are well known in theart. By way of example, a tissue culture containing organs has been usedto produce regenerated plants. U.S. Pat. Nos. 5,959,185, 5,973,234, and5,977,445 describe certain techniques, the disclosures of which areincorporated herein by reference.

Additional Breeding Methods

The invention is also directed to methods for producing a lettuce plantby crossing a first parent lettuce plant with a second parent lettuceplant where the first or second parent lettuce plant is a lettuce plantof variety ‘Cavendish’, ‘Clearwater’, or ‘Pensacola’. Further, bothfirst and second parent lettuce plants can come from lettuce variety‘Cavendish’, ‘Clearwater’, or ‘Pensacola’. Thus, any such methods usinglettuce variety ‘Cavendish’, ‘Clearwater’, or ‘Pensacola’ are part ofthe invention: selfing, backcrosses, hybrid production, crosses topopulations, and the like. All plants produced using lettuce variety‘Cavendish’, ‘Clearwater’, or ‘Pensacola’ as at least one parent arewithin the scope of this invention, including those developed fromvarieties derived from lettuce variety ‘Cavendish’, ‘Clearwater’, or‘Pensacola’. Advantageously, this lettuce variety could be used incrosses with other, different, lettuce plants to produce the firstgeneration (F₁) lettuce hybrid seeds and plants with superiorcharacteristics. The variety of the invention can also be used fortransformation where exogenous genes are introduced and expressed by thevariety of the invention. Genetic variants created either throughtraditional breeding methods using lettuce variety ‘Cavendish’,‘Clearwater’, or ‘Pensacola’, or through transformation of variety‘Cavendish’, ‘Clearwater’, or ‘Pensacola’ by any of a number ofprotocols known to those of skill in the art are intended to be withinthe scope of this invention.

The following describes breeding methods that may be used with lettucevariety ‘Cavendish’, ‘Clearwater’, or ‘Pensacola’ in the development offurther lettuce plants. One such embodiment is a method for developingvariety ‘Cavendish’, ‘Clearwater’, or ‘Pensacola’ progeny lettuce plantsin a lettuce plant breeding program, by: obtaining the lettuce plant, ora part thereof, of variety ‘Cavendish’, ‘Clearwater’, or ‘Pensacola’,utilizing said plant or plant part as a source of breeding material, andselecting a lettuce variety ‘Cavendish’, ‘Clearwater’, or ‘Pensacola’progeny plant with molecular markers in common with variety ‘Cavendish’,‘Clearwater’, or ‘Pensacola’ and/or with morphological and/orphysiological characteristics selected from the characteristics listedin the section entitled “Objective description of the variety‘Cavendish’”, “Objective description of the variety ‘Clearwater’”, or“Objective description of the variety ‘Pensacola’”. Breeding steps thatmay be used in the lettuce plant breeding program include pedigreebreeding, backcrossing, mutation breeding, and recurrent selection. Inconjunction with these steps, techniques such as RFLP-enhancedselection, genetic marker enhanced selection (for example, SSR markers),and the making of double haploids may be utilized.

Another method involves producing a population of lettuce variety‘Cavendish’, ‘Clearwater’, or ‘Pensacola’ progeny lettuce plants, bycrossing variety ‘Cavendish’, ‘Clearwater’, or ‘Pensacola’ with anotherlettuce plant, thereby producing a population of lettuce plants, which,on average, derive 50% of their alleles from lettuce variety‘Cavendish’, ‘Clearwater’, or ‘Pensacola’. A plant of this populationmay be selected and repeatedly selfed or sibbed with a lettuce varietyresulting from these successive filial generations. One embodiment ofthis invention is the lettuce variety produced by this method and thathas obtained at least 50% of its alleles from lettuce variety‘Cavendish’, ‘Clearwater’, or ‘Pensacola’. One of ordinary skill in theart of plant breeding would know how to evaluate the traits of two plantvarieties to determine if there is no significant difference between thetwo traits expressed by those varieties. For example, see Fehr and Walt,Principles of Variety Development, pp. 261-286 (1987). Thus theinvention includes lettuce variety ‘Cavendish’, ‘Clearwater’, or‘Pensacola’ progeny lettuce plants containing a combination of at leasttwo variety ‘Cavendish’, ‘Clearwater’, or ‘Pensacola’ traits selectedfrom those listed in the section entitled “Objective description of thevariety ‘Cavendish’”, “Objective description of the variety‘Clearwater’”, or “Objective description of the variety ‘Pensacola’”, orthe variety ‘Cavendish’, ‘Clearwater’, or ‘Pensacola’ combination oftraits listed in the Summary of the Invention, so that said progenylettuce plant is not significantly different for said traits thanlettuce variety ‘Cavendish’, ‘Clearwater’, or ‘Pensacola’ as determinedat the 5% significance level when grown in the same environmentalconditions. Using techniques described herein, molecular markers may beused to identify said progeny plant as a lettuce variety ‘Cavendish’,‘Clearwater’, or ‘Pensacola’ progeny plant. Mean trait values may beused to determine whether trait differences are significant, andpreferably the traits are measured on plants grown under the sameenvironmental conditions. Once such a variety is developed, its value issubstantial since it is important to advance the germplasm base as awhole in order to maintain or improve traits such as yield, diseaseresistance, pest resistance, and plant performance in extremeenvironmental conditions.

Progeny of lettuce variety ‘Cavendish’, ‘Clearwater’, or ‘Pensacola’ mayalso be characterized through their filial relationship with lettucevariety ‘Cavendish’, ‘Clearwater’, or ‘Pensacola’, as for example, beingwithin a certain number of breeding crosses of lettuce variety‘Cavendish’, ‘Clearwater’, or ‘Pensacola’. A breeding cross is a crossmade to introduce new genetics into the progeny, and is distinguishedfrom a cross, such as a self or a sib cross, made to select amongexisting genetic alleles. The lower the number of breeding crosses inthe pedigree, the closer the relationship between lettuce variety‘Cavendish’, ‘Clearwater’, or ‘Pensacola’ and its progeny. For example,progeny produced by the methods described herein may be within 1, 2, 3,4, or 5 breeding crosses of lettuce variety ‘Cavendish’, ‘Clearwater’,or ‘Pensacola’.

As used herein, the term “plant” includes plant cells, plantprotoplasts, plant cell tissue cultures from which lettuce plants can beregenerated, plant calli, plant clumps, and plant cells that are intactin plants or parts of plants, such as leaves, pollen, embryos,cotyledons, hypocotyl, roots, root tips, anthers, pistils, flowers,ovules, seeds, stems, and the like.

The use of the terms “a,” “an,” and “the,” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) are to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. Recitation of ranges of valuesherein are merely intended to serve as a shorthand method of referringindividually to each separate value falling within the range, unlessotherwise indicated herein, and each separate value is incorporated intothe specification as if it were individually recited herein. Forexample, if the range 10-15 is disclosed, then 11, 12, 13, and 14 arealso disclosed. All methods described herein can be performed in anysuitable order unless otherwise indicated herein or otherwise clearlycontradicted by context. The use of any and all examples, or exemplarylanguage (e.g., “such as”) provided herein, is intended merely to betterilluminate the invention and does not pose a limitation on the scope ofthe invention unless otherwise claimed. No language in the specificationshould be construed as indicating any non-claimed element as essentialto the practice of the invention.

While a number of exemplary aspects and embodiments have been discussedabove, those of skill in the art will recognize certain modifications,permutations, additions, and sub-combinations thereof. It is thereforeintended that the following appended claims and claims hereafterintroduced are interpreted to include all such modifications,permutations, additions, and sub-combinations as are within their truespirit and scope.

DEPOSIT INFORMATION

Lettuce Variety ‘Cavendish’

A deposit of the lettuce variety ‘Cavendish’ is maintained by Enza ZadenUSA, Inc., having an address at 7 Harris Place, Salinas, Calif. 93901,United States. Access to this deposit will be available during thependency of this application to persons determined by the Commissionerof Patents and Trademarks to be entitled thereto under 37 C.F.R. § 1.14and 35 U.S.C. § 122. Upon allowance of any claims in this application,all restrictions on the availability to the public of the variety willbe irrevocably removed by affording access to a deposit of at least2,500 seeds of the same variety with the National Collection ofIndustrial, Food and Marine Bacteria Ltd. (NCIMB Ltd), FergusonBuilding, Craibstone Estate, Bucksburn, Aberdeen, AB21 9YA, UnitedKingdom.

At least 2500 seeds of lettuce variety ‘Cavendish’ were deposited onSep. 11, 2018 according to the Budapest Treaty in the NationalCollection of Industrial, Food and Marine Bacteria Ltd (NCIMB Ltd),Ferguson Building, Craibstone Estate, Bucksburn, Aberdeen, AB21 9YA,United Kingdom. The deposit has been assigned NCIMB Number 43193. Accessto this deposit will be available during the pendency of thisapplication to persons determined by the Commissioner of Patents andTrademarks to be entitled thereto under 37 C.F.R. § 1.14 and 35 U.S.C. §122. Upon allowance of any claims in this application, all restrictionson the availability to the public of the variety will be irrevocablyremoved.

The deposit will be maintained in the NCIMB depository, which is apublic depository, for a period of at least 30 years, or at least 5years after the most recent request for a sample of the deposit, or forthe effective life of the patent, whichever is longer, and will bereplaced if a deposit becomes nonviable during that period.

The invention claimed is:
 1. A lettuce seed designated as ‘Cavendish’,representative sample of seed having been deposited under NCIMBAccession Number
 43193. 2. A lettuce plant produced by growing the seedof claim
 1. 3. A plant part from the plant of claim
 2. 4. The plant partof claim 3, wherein said part is a head, a leaf, or a portion thereof.5. The plant part of claim 4, wherein said part is a head.
 6. A lettuceplant having all the physiological and morphological characteristics ofthe lettuce plant of claim
 2. 7. A plant part from the plant of claim 6.8. The plant part of claim 7, wherein said part is a head, a leaf, or aportion thereof.
 9. The plant part of claim 8, wherein said part is ahead.
 10. An F₁ hybrid lettuce plant having ‘Cavendish’ as a parentwhere ‘Cavendish’ is grown from the seed of claim
 1. 11. A pollen grainor an ovule of the plant of claim
 2. 12. A tissue culture of the plantof claim
 2. 13. A lettuce plant regenerated from the tissue culture ofclaim 12, wherein the plant has all of the morphological andphysiological characteristics of a lettuce plant produced by growingseed designated as ‘Cavendish’, representative sample of seed havingbeen deposited under NCIMB Accession Number
 43193. 14. A method ofmaking lettuce seeds, said method comprising crossing the plant of claim2 with another lettuce plant and harvesting seed therefrom.
 15. A methodof making a lettuce variety ‘Cavendish’, said method comprisingselecting seeds from the cross of one ‘Cavendish’ plant with another‘Cavendish’ plant, a sample of ‘Cavendish’ lettuce seed having beendeposited under NCIMB Accession Number 43193.